Copied from 7-Zip Homepage:


License

7-Zip is open source software. Most of the source code is under the GNU LGPL license. The unRAR code is under a mixed license: GNU LGPL + unRAR restrictions. 

You can use 7-Zip on any computer, including a computer in a commercial organization. You don't need to register or pay for 7-Zip.
But you can make a donation to support further development of 7-Zip.


The main features of 7-Zip

High compression ratio in new 7z format with LZMA compression

Supported formats: 
Packing / unpacking: 7z, ZIP, GZIP, BZIP2 and TAR
Unpacking only: ARJ, CAB, CHM, CPIO, DEB, DMG, HFS, ISO, LZH, LZMA, MSI, NSIS, RAR, RPM, UDF, WIM, XAR and Z.

For ZIP and GZIP formats, 7-Zip provides a compression ratio that is 2-10 % better than the ratio provided by PKZip and WinZip

Strong AES-256 encryption in 7z and ZIP formats

Self-extracting capability for 7z format

Integration with Windows Shell

Powerful File Manager

Powerful command line version

Plugin for FAR Manager

Localizations for 74 languages


7-Zip works in Windows 98/ME/NT/2000/XP/Vista.
There is a port of the command line version to Linux/Unix.

On 7-Zip's Source Forge Page you can find a forum, bug reports, and feature request systems.


Compression ratio

Compression ratio results are very dependent upon the data used for the tests. Usually, 7-Zip compresses to 7z format 30-70% better than to zip format.
And 7-Zip compresses to zip format 2-10% better than most of other zip compatible programs.


Changelog:


7-Zip 9.05 Alpha:

7-Zip now can unpack MSLZ archives. 

Partial parsing for EXE resources, SWF and FLV. 

Some bugs were fixed. 

Some changes in interface. 


7-Zip 9.07 Beta

It's possible to specify Diff program in options (7-Zip File Manager). 

Some bugs were fixed. 



Don't use this beta version for important data.
Call "Test" command after each compressing operation. 



Comments from the uploader (olofolleola4):
If you wonder why it is called 9.04 instead of a version number like 4.66, that is because Igor Pavlov has decided to give this build the version number for the year 2009. The first 4.xx version were created in 2004.
So that's why it's called 9.04 :)


ED2K Link:
ed2k://|file|7z907-x64.msi|1299456|B2288F824F06403A3FD4DFE3AB738466|h=LXRFURIDZGK4PPUVSBXCHXTYIE2RK2LK|/